Merge pull request #2107 from sashayakovtseva/public-get-devices

Make get devices function public

libcontainer/devices/devices.go

@@ -7,11 +7,11 @@ import (
 	"path/filepath"
 
 	"github.com/opencontainers/runc/libcontainer/configs"
-
 	"golang.org/x/sys/unix"
 )
 
 var (
+	// ErrNotADevice denotes that a file is not a valid linux device.
 	ErrNotADevice = errors.New("not a device node")
 )
 
@@ -21,7 +21,8 @@ var (
 	ioutilReadDir = ioutil.ReadDir
 )
 
-// Given the path to a device and its cgroup_permissions(which cannot be easily queried) look up the information about a linux device and return that information as a Device struct.
+// Given the path to a device and its cgroup_permissions(which cannot be easily queried) look up the
+// information about a linux device and return that information as a Device struct.
 func DeviceFromPath(path, permissions string) (*configs.Device, error) {
 	var stat unix.Stat_t
 	err := unixLstat(path, &stat)
@@ -60,16 +61,19 @@ func DeviceFromPath(path, permissions string) (*configs.Device, error) {
 	}, nil
 }
 
+// HostDevices returns all devices that can be found under /dev directory.
 func HostDevices() ([]*configs.Device, error) {
-	return getDevices("/dev")
+	return GetDevices("/dev")
 }
 
-func getDevices(path string) ([]*configs.Device, error) {
+// GetDevices recursively traverses a directory specified by path
+// and returns all devices found there.
+func GetDevices(path string) ([]*configs.Device, error) {
 	files, err := ioutilReadDir(path)
 	if err != nil {
 		return nil, err
 	}
-	out := []*configs.Device{}
+	var out []*configs.Device
 	for _, f := range files {
 		switch {
 		case f.IsDir():
@@ -79,7 +83,7 @@ func getDevices(path string) ([]*configs.Device, error) {
 			case "pts", "shm", "fd", "mqueue", ".lxc", ".lxd-mounts", ".udev":
 				continue
 			default:
-				sub, err := getDevices(filepath.Join(path, f.Name()))
+				sub, err := GetDevices(filepath.Join(path, f.Name()))
 				if err != nil {
 					return nil, err
 				}